1. Field of the Invention
This invention relates to electronic, stringed musical instruments and more specifically, it relates to the use of resistance wires as strings which control the frequency of electronically generated sounds in such instruments.
2. Description of the Prior Art
It has been known to vary the resistance in a Wienbridge oscillator in an electrical circuit associated with a musical instrument. See U.S. Pat. No. 3,624,584. U.S. Pat. No. 3,626,350 discloses a means to produce a portamento chord by utilizing this principle.
U.S. Pat. No. 3,948,137 discloses prior art which allows the player of an instrument utilizing a voltage controlled oscillator to control sound effects by providing wave form, filter and gain controls.
U.S. Pat. No. 4,235,141 discloses an instrument wherein an apertured insulating strip is inserted between an electrically conducting strip and a resistive strip to only allow contact points at predetermined locations, thereby producing a tone at discrete selected values of frequency.
Electrically synthesized music is an increasingly popular art form in which substantial technological advances have been made. In the past, however, most of these advances could only be utilized in a keyboard type instrument excluding musicians skilled primarily in the playing of stringed instruments.
A known attempt to provide a voltage controlled electronic stringed instrument is U.S. Pat. No. 4,038,897. In this patent, a guitar or other fretted instrument is used to produce input signals for a voltage-controlled tone generator or the guitar can be used in the conventional fashion by operating a switch. Each string-fret pair has an assigned musical tone. Voltages analogous to said tones are applied to the instruments frets so as to apply such voltage to the strings when the strings contact the frets.
Such systems have several major limitations. Firstly, the invention is limited to fretted stringed instruments. Additionally, complicated wiring of resistors to each fret is required in order to provide each with the proper voltage value. Finally, providing the voltage to electrically conducting frets appears to foreclose the possibility of playing chords without fret segmentation.
There remains, therefore, a need for a stringed electronic instrument which provides effective frequency control in either fretted or unfretted string instruments employing the strings as resistance and a means for playing chords whether or not frets are desired.